Hostname: page-component-78c5997874-mlc7c Total loading time: 0 Render date: 2024-11-10T12:54:56.507Z Has data issue: false hasContentIssue false
  • English
  • Français

Determining Mechanical Properties of Escherichia Coli by Nanoindentation

Published online by Cambridge University Press:  10 February 2012

C. A. Wright ,
C.J. Sullivan ,
B. Crawford ,
L.D. Britt ,
M.A. Mamun  and
A.A. Elmustafa
C. A. Wright
Affiliation:
Department of Mechanical and Aerospace Engineering, Old Dominion University, Norfolk, Virginia 23529, USA Applied Research Center, Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA
C.J. Sullivan
Affiliation:
Department of Surgery, Eastern Virginia Medical School, Norfolk, VA 23501
B. Crawford
Affiliation:
Nanomechanics, Inc., Oak Ridge, TN 37830
L.D. Britt
Affiliation:
Department of Surgery, Eastern Virginia Medical School, Norfolk, VA 23501
M.A. Mamun
Affiliation:
Department of Mechanical and Aerospace Engineering, Old Dominion University, Norfolk, Virginia 23529, USA Applied Research Center, Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA
A.A. Elmustafa
Affiliation:
Department of Mechanical and Aerospace Engineering, Old Dominion University, Norfolk, Virginia 23529, USA Applied Research Center, Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA
Get access

Abstract

Escherichia coli, like other gram-negative bacteria, is protected from the surrounding harsh environment by a cell wall consisting of the peptidoglycan and outer membrane. Whereas the cytoplasmic membrane is the selective barrier, the cell wall provides mechanical strength for the cell. As bacteria navigate various environments, osmotic pressure can change dramatically due to changes in local solute concentration. The peptidoglycan together with the cellular proteins mitigates the osmotic stress that would otherwise cause lysis. The mechanical properties of E. coli cells and its individual layers have been largely indeterminable until the recent development of probe-based measurement tools. Since their invention, scientists have reported significant data measuring elasticity, modulus, and stiffness using atomic force microscopy (AFM). Fundamentally, in order to determine these mechanical properties through probe-based techniques, the contact area and load should be well defined. The load can be precisely calculated through the AFM cantilever spring constant. However, the silicon tip contact area can only be estimated, potentially leading to compounding uncertainties. Therefore, we developed a methodology to determine nanomechanical properties of E. coli using a nanoindenter.

Keywords

nano-indentationbiologicalbiomaterial
Type
Research Article
Information
MRS Online Proceedings Library (OPL) , Volume 1424: Symposium SS – Properties and Processes at the Nanoscale Nanomechanics of Material Behavior , 2012 , mrsf11-1424-ss04-02-oo03-02
Copyright
Copyright © Materials Research Society 2012

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

1. Arnoldi, M., et al. ., Bacterial turgor pressure can be measured by atomic force microscopy. Physical Review E (Statistical Physics, Plasmas, Fluids, and Related Interdisciplinary Topics), 2000. 62(Copyright 2000, IEE): p. 1034–44.Google Scholar
2. Cerf, A., et al. ., Nanomechanical properties of dead or alive single-patterned bacteria. Langmuir, 2009. 25(Compendex): p. 5731–5736.Google Scholar
3. Vadillo-Rodriguez, V., Beveridge, T.J., and Dutcher, J.R., Surface Viscoelasticity of Individual Gram-Negative Bacterial Cells Measured Using Atomic Force Microscopy. J. Bacteriol, 2008. 190: p. 4225–4232.Google Scholar
4. Burnham, N.A., et al. ., Comparison of calibration methods for atomic-force microscopy cantilevers. Nanotechnology, 2003. 14(1): p. 1–6.Google Scholar
5. Butt, H.J. and Jaschke, M., Calculation of thermal noise in atomic force microscopy. Nanotechnology, 1995. 6(1): p. 1–7.Google Scholar
6. Hutter, J.L. and Bechhoefer, J., Calibration of atomic-force microscope tips. Review of Scientific Instruments, 1993. 64(7): p. 1868–73.Google Scholar
7. Kiernan, J., Formaldehyde, formalin, paraformaldehyde and glutaraldehyde: What they are and what they do. Microscopy Today, 2000.00-1: p. 8–12.Google Scholar
8. Braet, F., , C.R., Wisse, E., Radmacher, M., Comparison of fixed and living endothelial cells by atomic force microscopy. Applied Physics a-Materials Science & Processing, 1997. 66: p. S575–S578.Google Scholar
9. Hutter, J.L., Chen, J., Wan, W. K., Uniyal, S., Leabu, M., and Chan, B. M. C., Atomic force microscopy investigation of the dependence of cellular elastic moduli on glutaraldehyde fixation. Journal of Microscopy-Oxford, 2005. 219: p. 61–68.Google Scholar